4-54703788-C-T

Position:

chr4-54703788-C-T

Variant summary

Our verdict is Benign. Variant got -8 ACMG points: 1P and 9B. PP2BP4_StrongBP6BS2

The NM_000222.3(KIT):c.821C>T(p.Thr274Met) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00042 in 1,613,308 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 12/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.00036 ( 1 hom., cov: 32)

Exomes 𝑓: 0.00043 ( 0 hom. )

Consequence

KIT
NM_000222.3 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:7B:4

Conservation

PhyloP100: 0.0970

Variant links:

Genes affected

KIT (HGNC:6342): (KIT proto-oncogene, receptor tyrosine kinase) This gene encodes a receptor tyrosine kinase. This gene was initially identified as a homolog of the feline sarcoma viral oncogene v-kit and is often referred to as proto-oncogene c-Kit. The canonical form of this glycosylated transmembrane protein has an N-terminal extracellular region with five immunoglobulin-like domains, a transmembrane region, and an intracellular tyrosine kinase domain at the C-terminus. Upon activation by its cytokine ligand, stem cell factor (SCF), this protein phosphorylates multiple intracellular proteins that play a role in in the proliferation, differentiation, migration and apoptosis of many cell types and thereby plays an important role in hematopoiesis, stem cell maintenance, gametogenesis, melanogenesis, and in mast cell development, migration and function. This protein can be a membrane-bound or soluble protein. Mutations in this gene are associated with gastrointestinal stromal tumors, mast cell disease, acute myelogenous leukemia, and piebaldism. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, May 2020]

KIT links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -8 ACMG points.

PP2

Missense variant in gene, where missense usually causes diseases (based on misZ statistic), KIT. . Gene score misZ 2.5806 (greater than the threshold 3.09). Trascript score misZ 4.1549 (greater than threshold 3.09). GenCC has associacion of gene with piebaldism, gastrointestinal stromal tumor, mastocytosis, cutaneous mastocytosis.

BP4

Computational evidence support a benign effect (MetaRNN=0.033516467).

BP6

Variant 4-54703788-C-T is Benign according to our data. Variant chr4-54703788-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 41604.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=1, Benign=3, Uncertain_significance=5}. Variant chr4-54703788-C-T is described in Lovd as [Likely_benign].

BS2

High AC in GnomAd4 at 54 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
KIT	NM_000222.3 linkuse as main transcript	c.821C>T	p.Thr274Met	missense_variant	5/21	ENST00000288135.6	NP_000213.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
KIT	ENST00000288135.6 linkuse as main transcript	c.821C>T	p.Thr274Met	missense_variant	5/21	1	NM_000222.3	ENSP00000288135	P4	P10721-1

Frequencies

GnomAD3 genomes

AF:

0.000355

AC:

AN:

151952

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000193

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000262

Gnomad ASJ

AF:

0.00490

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.000353

Gnomad OTH

AF:

0.000478

GnomAD3 exomes

AF:

0.000490

AC:

123

AN:

251244

Hom.:

AF XY:

0.000412

AC XY:

AN XY:

135782

show subpopulations

Gnomad AFR exome

AF:

0.0000615

Gnomad AMR exome

AF:

0.000896

Gnomad ASJ exome

AF:

0.00486

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.0000462

Gnomad NFE exome

AF:

0.000299

Gnomad OTH exome

AF:

0.00114

GnomAD4 exome

AF:

0.000427

AC:

624

AN:

1461240

Hom.:

Cov.:

AF XY:

0.000406

AC XY:

295

AN XY:

726970

show subpopulations

Gnomad4 AFR exome

AF:

0.000120

Gnomad4 AMR exome

AF:

0.000872

Gnomad4 ASJ exome

AF:

0.00410

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.0000562

Gnomad4 NFE exome

AF:

0.000386

Gnomad4 OTH exome

AF:

0.000679

GnomAD4 genome

AF:

0.000355

AC:

AN:

152068

Hom.:

Cov.:

AF XY:

0.000323

AC XY:

AN XY:

74322

show subpopulations

Gnomad4 AFR

AF:

0.000193

Gnomad4 AMR

AF:

0.000262

Gnomad4 ASJ

AF:

0.00490

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.000353

Gnomad4 OTH

AF:

0.000473

Alfa

AF:

0.000482

Hom.:

Bravo

AF:

0.000385

TwinsUK

AF:

0.000539

AC:

ALSPAC

AF:

0.000519

AC:

ESP6500AA

AF:

0.00

AC:

ESP6500EA

AF:

0.000581

AC:

ExAC

AF:

0.000461

AC:

Asia WGS

AF:

0.000577

AC:

AN:

3478

EpiCase

AF:

0.000491

EpiControl

AF:

0.000474

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:7Benign:4

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

not provided

Uncertain:3

Uncertain significance, no assertion criteria provided	research	Biesecker Lab/Clinical Genomics Section, National Institutes of Health	Jul 13, 2012	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Institute for Clinical Genetics, University Hospital TU Dresden, University Hospital TU Dresden	Nov 03, 2021	- -
Uncertain significance, no assertion criteria provided	clinical testing	Department of Pathology and Laboratory Medicine, Sinai Health System	-	The KIT p.Thr274Met variant was identified in dbSNP (ID: rs138585275), Cosmic (FATHMM predicted neutral; score=0.04) and in ClinVar (classified as a VUS by CSER_CC_NCGL University of Washington Medical Centre and Biesecker Lab/Human Development Section NIH and as benign by Invitae for gastrointenstinal stroma tumor). The variant was also identified in control databases in 131 of 282620 chromosomes (1 homozygous) at a frequency of 0.000464 increasing the likelihood this could be a low frequency benign variant (Genome Aggregation Database Feb 27, 2017). The variant was observed in the following populations: Ashkenazi Jewish in 49 of 10364 chromosomes (freq: 0.004728), Other in 7 of 7220 chromosomes (freq: 0.00097), Latino in 33 of 35430 chromosomes (freq: 0.000931), European (non-Finnish) in 37 of 128978 chromosomes (freq: 0.000287), African in 4 of 24958 chromosomes (freq: 0.00016) and European (Finnish) in 1 of 25120 chromosomes (freq: 0.00004); it was not observed in the East Asian and South Asian populations. The variant occurs outside of the splicing consensus sequence and in silico or computational prediction software programs (SpliceSiteFinder, MaxEntScan, NNSPLICE, GeneSplicer) do not predict a difference in splicing at the variant location. The p.Thr274 residue is not conserved in mammals and computational analyses (PolyPhen-2, SIFT, AlignGVGD, BLOSUM, MutationTaster) provide inconsistent predictions regarding the impact to the protein. This information is not very predictive of pathogenicity. In summary, based on the above information the clinical significance of this variant cannot be determined with certainty at this time. This variant is classified as a variant of uncertain significance. -

Gastrointestinal stromal tumor

Uncertain:1Benign:1

Uncertain significance, criteria provided, single submitter	clinical testing	Illumina Laboratory Services, Illumina	Apr 27, 2017	This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). Publications were found based on this search. However, the evidence from the literature, in combination with allele frequency data from public databases where available, was not sufficient to rule this variant in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -
Benign, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Feb 01, 2024	- -

Hereditary cancer-predisposing syndrome

Uncertain:1Benign:1

Likely benign, criteria provided, single submitter	curation	Sema4, Sema4	Apr 20, 2021	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	Nov 26, 2018	The p.T274M variant (also known as c.821C>T), located in coding exon 5 of the KIT gene, results from a C to T substitution at nucleotide position 821. The threonine at codon 274 is replaced by methionine, an amino acid with similar properties. This amino acid position is poorly conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Piebaldism

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Apr 27, 2017

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases did not allow this variant to be ruled in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -

Gastrointestinal stromal tumor, familial

Uncertain:1

Uncertain significance, criteria provided, single submitter

research

CSER _CC_NCGL, University of Washington

Jan 01, 2016

- -

not specified

Benign:1

Benign, criteria provided, single submitter

clinical testing

Genetic Services Laboratory, University of Chicago

Mar 29, 2021

- -

Mastocytosis

Benign:1

Benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Apr 27, 2017

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases was too high to be consistent with this variant causing disease. Therefore, this variant is classified as benign. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.083

BayesDel_addAF

Benign

-0.46

BayesDel_noAF

Benign

-0.51

CADD

Benign

DANN

Uncertain

1.0

DEOGEN2

Uncertain

0.44

.;T

Eigen

Benign

-0.28

Eigen_PC

Benign

-0.45

FATHMM_MKL

Benign

0.035

LIST_S2

Benign

0.78

T;T

M_CAP

Benign

0.020

MetaRNN

Benign

0.034

T;T

MetaSVM

Benign

-1.1

MutationAssessor

Uncertain

2.2

M;M

MutationTaster

Benign

1.0

N;N

PrimateAI

Benign

0.27

PROVEAN

Uncertain

-3.7

D;D

REVEL

Benign

0.038

Sift

Uncertain

0.0050

D;D

Sift4G

Uncertain

0.014

D;D

Polyphen

0.94

P;D

Vest4

0.14

MVP

0.47

MPC

0.64

ClinPred

0.076

GERP RS

1.2

Varity_R

0.053

gMVP

0.91

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.0

Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over